From DE 42 16 210 A1, a pneumatic knuckle joint lifting gear for a deep-drawing packaging machine is known in which all drive components and the knuckle joint mechanism are disposed underneath the movable tool. In deep-drawing packaging machines, the working height or the subfilm transport level is located at a height of approximately 900 mm above ground. With such a working height and a knuckle joint lifting gear, cavities of a maximum drawing depth of about 200 mm may be manufactured.
From U.S. Pat. No. 5,205,110, an electromotive lifting gear for a deep-drawing packaging machine is known in which an electric motor is disposed in the production direction downstream of a forming station and outside the travel of a mould bottom part, and the mould bottom part is lifted and lowered by means of the lifting gear. The drive energy of the electric motor is transmitted to a connecting rod by means of drive belts, the connecting rod in turn converting its rotary motion into a vertical motion of the mould bottom part by means of a connecting link guide. In the process, the connecting rod is moved into a dead center position where the mould bottom part is located in its working position to be able to take up high closure forces in cooperation with the die top.
From DE 10 2008 023 319 A1, a lifting gear for a tray sealer is known wherein the lifting gear comprises two spindles which are driven via a sprocket belt by a servomotor. All drive and transmission components are disposed underneath the sealing tool bottom.
Lifting gears of the known prior art have the disadvantage that by the arrangement of drive components underneath a tool to be moved vertically, the travel of the latter is very restricted, or that the tool to be moved may not be held in any position such that it is able to take up closure forces in the form of retention forces occurring with the cooperating upper tool.